Sonic earth cutting machine



6. 1969 w. a GOODMAN 3,463,549

SONIC EARTH CUTTING MACHINE I f Filed Aug. 11, 1967 28heets-Sheet1 25 4 26 4 C l" L J 22 I FIG. 2

INVENTOR:

w. a. GOODMAN HIS ATTORNEY Aug. 26, 1969 Filed Aug. 11, 1967 w. B. GOODMAN some EARTH CUTTING MACHINE 2 Sheets-Sheet 2 F|G.T 22\ FIG. 4 2e 2o FIG.8 F|G.5

INVENTOR: F|G.6

HI ATTORNEY United States Patent U.S. Cl. 299-37 6 Claims ABSTRACT OF THE DISCLOSURE A sonic resonant device is carried by a handling mechanism such as a hoisting crane mounted on a carrier vehicle. An elongated elastic cutting bar is rigidly coupled to the resonant driver and is manipulated into position and driven downward into a competent earth formation adjacent an open face thereof to break or separate chunks of the earth material from the earth formation. Earth engaging cutting means is carried on the lower end of the cutting bar and includes earth engaging guide means which is cooperative with the earth formation to prevent lateral displacement of the cutting means.

BACKGROUND OF THE INVENTION Field of the invention The present invention relates to the art of excavating and pertains more particularly to methods and apparatus for using sonic energy for cutting and separating or breaking awa chunks of competent earth formations.

In excavating for the emplacement of structure such as foundations for buildings and bridges and for the laying of pipes and cables, competent earth formations are often encountered. Some of such formations are generally too hard for conventional excavating apparatus such as scoops, buckets and clamshells. It then becomes necessary to use the expensive and time-consuming rock breaking tools such as jack hammers because no adequate tools or apparatus are available to bridge the gap between the above prior art devices.

Summary of the invention It is a primary object of the present invention to provide an apparatus for cutting competent earth formations that bridges the gap between prior known devices.

It is a further object of the present invention to provide an earth cutting apparatus that utilizes the principles of sonic energy for breaking up competent earth formations.

In accordance with the present invention a substantially vertically oriented cutting bar is sonically driven into a competent earth formation substantially parallel and adjacent the open face of said competent earth formation substantially simultaneously cutting and breaking away portions of the formation.

Brief description of the drawings Other objects will become apparent from the following description when read in connection with the accompanying drawings in which:

FIGURE 1 is a diagrammatic side elevational view of a sonic earth cutting apparatus in accordance with the invention;

FIGURE 2 is a cross sectional view of one embodiment of the cutting bar of the invention;

FIGURE 3 is a schematic top view of a cutting pattern in accordance with this invention;

FIGURE 4 is a partial sectional view taken along lines 4-4 of FIGURE 2;

FIGURE 5 is a side elevational view partially in section of a second embodiment of the cutting bar of the present invention;

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FIGURE 6 is a sectional view of a third embodiment of the cutting bar of the present invention;

FIGURE 7 is a sectional view of the cutting bar of FIGURE 6;

FIGURE 8 is a cross sectional view of a fourth embodiment of the cutting bar of the present invention.

FIGURE 9 is a cross sectional view taken along line 99 of FIGURE 8.

Description of the preferred embodiments The present invention makes use of conventional sonic pile drivers such as that more particularly detailed in US. Patent No. 3,195,659. Reference is made to the aforementioned US. patent for details of a sonic pile driver suitable for use in the present invention. In FIGURE 1 is schematically illustrated a suitable sonic pile driver for use in the present invention. As shown in FIGURE 1, a suitable mobile carrier vehicle 11 having tracks 12 supports a boom-13 from pivotal mounting means 15 attached at pivotal means 16 to boom 13. A sonic vibration generator 17 is mounted on guide structure 15 in any suitable manner such as on rails, now shown, for vertical movement therealong. A cutting tool in the form of an elongated elastic bar 18 is rigidly coupled in any suitable manner such as by clamp or flange 19 to the sonic generator 17 or oscillator.

The cutting bar 18 has a cutting point or edge especially adapted to engage a competent earth formation near an open'space S and cut the formation along substantially parallel to the face F and simultaneously chip or break chunks C out of the competent formation into the open space S. The cutting bar 18 is preferably of elongated configuration and constructed of a suitable elastic material such as a good grade of alloy steel. The cutting bar 18 has formed at its lower end a cutting point or edge 20 and a chip breaker or separator 21 sloping outward from the point to break or separate chunks or masses of the competent earth material from the formation. A fairing 22 to facilitate withdrawal is connected to the cutting bar 18 above the chip breaker 21.

The cutting bar may have any number of suitable crosssectional configurations. Illustrated in FIGURE 2 is a preferred cross-sectional configuration for the cutting bar. As illustrated in FIGURE 2, the cutting bar 18 has a substantially H or I configuration. This configuration offers a number of interesting and important features that would not be present in a straight or flat cutting bar. One important feature as can be readily seen in FIGURES 4 and 5 is a forwardly extending cutting edge 23 and a rearwardly extending cutting edge 24. The forwardly extending cutting edge 23 makes it possible to cut the earth formation in such a pattern that the chip C is completely severed or sheared on all sides from the formation. As seen in FIGURE 3 the cutting pattern forms a complete loop of cut around the chip C so that it is easily forced outward and separated from the face of the formation and into the excavation S or other similar open space adjacent the face of the formation. In this construction a pair of guide and reinforcing flanges 25 extend longitudinally along the length of the forward side of the cutting bar. Flanges 26 serve as reinforcing and guide means extending longitudinally along the length of the rearward portion of the cutter bar. The rearward extending cutting means 24 forms a cut extending backward from the major cutting face or point 20 of the bar and makes possible a larger cut chip C as well as cutting guide ways for guide means 26. The guide means 26 engages the slots in the formation and assures lateral stability and prevents wandering of the cutting bar as it travels downward. This guide means also assures a more accurate cut by preventing the cutter from moving laterally into an adjacent open space.

A further embodiment of the cutting tool or bar is shown in FIGURE 5 in which the cutting section or portion 27 of the tool may have any desired configuration for a suitable length and connected in any suitable manner such as by welding to a resonator bar 28. The end of the resonator bar 28 is then rigidly coupled in any suitable manner such as by clamp 29 to the vibration generator 17. In practice it may be generally preferably to match the two portions of the cutter bar such that they have the same resonant characteristics. That is, a standing wave of the proper frequency may be included in the bar throughout its length as though it were the same from end to end. It may also be desirable to construct the cutting bar such that only the resonant member 27 vibrates at the resonant frequency and the cutting portion is bodily vibrated or carried bodily along with the end of the resonator member 28 as it vibrates. This may be desirable where, for example, the trench or excavation is shallow or where the cutting section 26 must be constructed of a high grade tool steel or other such material having good wear characteristics.

The cutting section of the cutting tool or bar may have any number of suitable cross-sectional configurations such as, for example, a C or channel configuration as shown in FIGURES 6 and 7. In FIGURES 6 and 7 is shown a cutting bar having a cutting section 30 with a C or channel cross-sectional configuration. The cutting bar embodying a cutting section having this configuration may be constructed in the manner suggested with respect to the embodiments of FIGURES 1-5. The cutting section 30 has a major cutting edge 31 and a forwardly extending cutting edge 32. A chip breaker or separator 33 slopes outward and upward from the major cutting edge 31. A fairing 34 slopes from the top of the ship breaker 33 back to the main portion of the cutting section. A pair of guide and re-inforcing flanges 35 extend longitudinally along the cutting bar from the cutting edges 32.

A typical cutting pattern for the cutting bar shown in FIGURES 6-7 is shown in FIGURE 8. I

An alternate form of the cutting section of the cutting bar of the present invention may be constructed in accordance with that shown in FIGURES 8 and 9. Such a cutting section is essentially made up of a plurality of the cutting sections of either of the previous embodiments. Designated by reference numeral 36 it could have a cross-sectional configuration substantially shown in FIGURE 8. As more fully detailed in FIGURE 9, the first section of the cutting bar, that is, that portion that would appear adjacent the face of the formation, would have a longitudinal cross-section substantially as that of the cross-section in the previous embodiment. Windows 37 and 38 are formed in the webbing of each of the sections to permit chips or chunks of earth material to be diverted therethrough from the adjacent channel into the open space in the earth formation. Chip breakers or earthdiverting means 39 and 40 through channels adjacent the windows to break and divert the material through the window. The cutting section in accordance with this modification permits a greater area of cut to be taken each time the cutting tool is driven downward into the earth formation.

Operation In operation of the present invention, the movable earth cutting machine 11 is moved to the location of the desired excavation as shown in FIGURE 1. A proper earth-cutting tool is then selected and secured by any suitable means such as flange or clamp 19 to a driving head 17. The machine is then moved into position adjacent an open space S in the earth formation E and the cutting section of the cutting bar is then manipulated into position and lowered into contact with the competent mass near the edge or face F forming the open space S. The cutting tool 18 is then sonically driven downward substantially parallel to the face F of the formation E. Briefly, the sonic driving of an elongated elastic member into the earth comprises setting up in said member longitudinally oriented elastic standing waves, under the action of which the member cyclically elongates and contacts at resonant frequency. Under such conditions, the ends of the bar at an anti-node, i.e., place of maximum velocity and displacement. With the forward end of the cutter member in engagement with the earth, the cyclic impacts thereof forces the earth formation to give away as well as fluidizes the immediately adjacent soil such that the weight of sonic generator and the cutter member easily forces the cutter member downward into the formation. As shown in FIGURE 1, the chip breaker or separator 21 forces the chip C outward from the formation E into the space S to be removed in any conventional manner such as by shovel. After the cutting bar is driven to the desired ,depth, it is then withdrawn and repositioned at a point laterally offset from the previous cut generally a distance the width of the cutting bar as shown in FIGURE 3. The cutting bar is then driven downward to the predetermined depth and the above procedure is repeated until the desired width portion is cut out of the formation. The machine is then moved forward and the above cutting procedure is again repeated until the desired trench has. been cut through the formation.

I claim as my invention:

1. In an earth cutting machine comprising:

an elongated elastic cutting bar means;

earth-engaging cutting means carried on the forward end of said elastic bar;

earth-engaging guide means carried by said cutting means, and cooperative with an earth formation to prevent lateral displacement of said cutting means during the cutting of said formation;

a sonic vibration generator coupled to the other end of said bar and adapted to set up resonant vibrations in said bar; and,

supporting and manipulating means operatively connected to said sonic vibration generator for manipulating said cutting bar into suitable earth-engaging relationship.

2. The apparatus of claim 1 including:

chip breaking means carried on said forward end of said bar adjacent said cutting edge.

3. Theapparatus of claim 1 wherein:

said cutting means has a substantially H cross-sectional configuration.

4. The apparatus of claim 3 wherein:

said cutting means and said elastic bar have substantially the same cross-sectional configuration.

5. The apparatus of claim 1 wherein:

said cutting means has a substantially C cross-sectional configuration.

6. The apparatus of claim 5 wherein:

said cutting means and said elastic bar have substantially the same cross-sectional configuration.

References Cited UNITED STATES PATENTS 2,990,226 6/ 1961 Muller et al 173-49 3,033,543 5/1962 Bodine 299-14 3,278,235 10/1966 Bergstrom 299-14 X 3,394,766 7/1968 Lebelle 173-49 ERNEST R. PURSER, Primary Examiner US. Cl. X.R. 

